Genesis does not identify them as angels but as men.
Looking up, he saw three men standing near him.
Gen 18:2
Moving further on to Gen 18:9-12, the 3 men inquire about Sarah, Abraham's wife. One of them goes so far as to say he will return next year when Sarah will have a son. Meanwhile, Sarah has been listening and begins to laugh (because she is advanced in years). In Gen 18:13, it reads: "But the LORD said to Abraham:" If you move forward to Gen. 19:24 the text says that the LORD rains down fire and brimstone from the LORD in heaven. This seems to support the Trinity or at the very least a multiplicity in the Godhead.
Gen 16 has a better account of the angel of the Lord.
The revelation of God to our minds and spirits (if we have His Spirit in us, that is) lets us know they were angels, not ordinary men. Angels apparently have an appearance similar to “men” in some cases. But, continue to go on a pointless rabbit trail if you like. In the end, all knowledge will be revealed, and we will see that this is a meaningless discussion to our purposes here and now. I shouldn’t have made my first one-word comment of “No” on a catholic thread anyway. That was my pointless mistake.